What is the grub-pc?

[millisami]

I fired up a new box (vagrant 0.6.8) and I was updating the box with aptitude and I get this visual box asking me where to install it?

What is this thing and which option do I have to choose?

Package configuration                                                                                   
 ┌──────────────────────────────────────────────┤ Configuring grub-pc ├──────────────────────────────────────────────┐  
 │ The GRUB boot loader was previously installed to a disk that is no longer present, or whose normally unique       │  
 │ identifier has changed for some reason. It is important to make sure that the installed GRUB stays in sync with   │  
 │ other components such as grub.cfg or with newer Linux images it will have to load, and so you should check again  │  
 │ to make sure that GRUB is installed to the appropriate boot devices.                                              │  
 │                                                                                                                   │  
 │ If you're unsure which drive is designated as boot drive by your BIOS, it is often a good idea to install GRUB    │  
 │ to all of them.                                                                                                   │  
 │                                                                                                                   │  
 │ Note: It is possible to install GRUB to partition boot records as well, and some appropriate partitions are       │  
 │ offered here.  However, this forces GRUB to use the blocklist mechanism, which makes it less reliable, and        │  
 │ therefore is not recommended.                                                                                     │  
 │                                                                                                                   │  
 │ GRUB install devices:                                                                                             │  
 │                                                                                                                   │  
 │    [ ] /dev/sda (42949 MB, VBOX_HARDDISK)                                                                         │  
 │    [ ] - /dev/sda1 (41420 MB, /)                                                                                  │  
 │                                                                                                                   │  
 │                                                                                                                   │  
 │                                                      <Ok>

[mitchellh]

This is strange. I haven't seen this before. I would simply update Vagrant (to 0.7.0), redownload the latest box, and try again. I have a feeling this may be a strange issue with version compatibility.

Let me know if this helps. Also ,what OS are you on?

[mitchellh]

Going to close this due to inactivity. I'll happily reopen with more info. :)

[zimbatm]

Just to answer the questions:

What is this thing ? grub is the bootloader used by most linux distros. It is needed to start the operating system.

Which option do I have to choose ? Use /dev/sda.

(implicit) Why is this happening ? grub needs to install some software at the start of the disk/partition (see /dev/sda). When the package gets an upgrade, dpkg will ask you where to install that upgrade.

[millisami]

Well, that was my stupidity. I was running a RailsReady script published at ChangeLog.com directly in the vagrant VM.

[d2kagw]

Thought I'd let you guys know that i've seen this start to pop up with the Precise64 box.
There's a grub update that gets installed when you do an apt-get upgrade that causes the above mentioned modal to present itself.

Really plays havoc with my Chef bootstrap file :/

[vitch]

I'm seeing this too on the Precise64 box when I apt-get upgrade...

Choosing /dev/sda seems to allow things to work - I've successfully vagrant halt and vagrant up since running it...

[cheapRoc]

The fix I had to use within my chef bootstrap file for Vagrant was...

apt-get -y remove grub-pc
apt-get -y install grub-pc
grub-install /dev/sda # precaution
update-grub 
# now start bootstrapping and upgrading your system packages
apt-get -y upgrade
...

[fringd]

sudo DEBIAN_FRONTEND=noninteractive apt-get -y -o Dpkg::Options::="--force-confdef" -o Dpkg::Options::="--force-confold" dist-upgrade

was the magic words for me... seems to be an ubuntu problem, maybe apt-chef is the proper place to report it?

[intval]

After installing grub to /dev/sda all consequent boots get into Memtest and would never go back to the OS itself.

[Valloric]

I just got this same issue after running sudo apt-get update && sudo apt-get upgrade with the vanilla precise64 box. Installing GRUB to /dev/sda (the first option, has VBOX_HARDDISK) worked fine. VM rebooted without issues.

Vagrant version: 1.4.3
Output of uname -a in VM: Linux precise64 3.2.0-23-generic #36-Ubuntu SMP Tue Apr 10 20:39:51 UTC 2012 x86_64 x86_64 x86_64 GNU/Linux
Host machine OS X 10.9.1, uname -a: Darwin <redacted> 13.0.0 Darwin Kernel Version 13.0.0: Thu Sep 19 22:22:27 PDT 2013; root:xnu-2422.1.72~6/RELEASE_X86_64 x86_64
VirtualBox version: 4.3.6 r91406

[JonLevy]

I am having the same issue with precise64. I am running in gui mode with ubuntu-desktop installed through apt-get, and am updating through the update manager.

The update manager tells me that the disk grub-pc was previously installed on is no longer present, and gives me the option to install it one of three places (/dev/sda VBOX_HARDISK, /dev/sda1, or /dev/dm-0). However, attempts to install in any of those places fail. Update manager gives me the option to continue without installing grub-pc. When I do that, things seem to go through without a problem and restart works.

I don't know what all this means, but it doesn't inspire the greatest confidence . . . that said, it seems to be working. :)

Vagrant version 1.4.3. Host OSX 10.9.1. Virtualbox 4.3.6 r91406.

[calinpupaza]

I had the same problem on a precise64 box after adding apt-get upgrade to the bootstrapping script.
My solution was to use debconf to preconfigure the selection to /dev/sda prior to apt-get update and upgrade.
And after reboot everything worked OK.

echo "set grub-pc/install_devices /dev/sda" | debconf-communicate
apt-get -y -qq update
apt-get -y -qq upgrade

This tutorial was helpful: http://feeding.cloud.geek.nz/posts/manipulating-debconf-settings-on/

Vagrant 1.5.1 VirtualBox 4.3.10 MacOX X 10.9.2